There is a middle ground here. If you set COLLOCATION=NO, it will drastically affect your RESTORE performance. Over time, you could in theory have to mount EVERY TAPE to do a full restore of a client.
That is why collocation is a good thing. But collocation will, by default, put each client on its own tape, thereby using a LOT of tapes. The alternative is to control collocation by setting the MAXSCRATCH value for your TAPEPOOL. Assume you are starting out with a new TSM server; if you have 80 clients and set MAXSCRATCH to 40, TSM will stack 2 clients per tape. This is a good thing, too. You get 90% of the benefits of collocation, with only half the tapes. This is a very common thing to do; there are plenty of sites that have more clients than slots in their library! The drawback is that you have to check on the value of MAXSCRATCH often. As you get more tapes in FULL status (assuming you are like the rest of us and your site is CONSTANTLY growing its storage farm), you have to keep increasing the value of MAXSCRATCH. That's easy: update stgpool TAPEPOOL maxscratch=xxx. Or do it from the admin GUI. What I do is: 1) Decide whether you want to stack 2, 3, etc. clients per tape. For example, pick TWO. 2) Then the number of TAPEPOOL tapes you wand to be in FILLING status is #clients/TWO. 3) Count the number of tapes in TAPEPOOL that are already FULL. 3) Set TAPEPOOL MAXSCRATCH to: DESIRED FILLING + ALREADY FULL. Check it one a week (or more often if you fill up a lot of tapes daily) and add more to MAXSCRATCH as tapes get full. Regarding COPYPOOL, I don't see any reason to collocate that at all. Wanda Prather "I/O, I/O, It's all about I/O" -(me) -----Original Message----- From: ADSM: Dist Stor Manager [mailto:[EMAIL PROTECTED] On Behalf Of Roark Ludwig Sent: Thursday, August 25, 2005 7:56 PM To: ADSM-L@VM.MARIST.EDU Subject: Re: Question about Space Reclamation.. I have been handed a TSM system in the past week that has been running for a year. IT has collocation = yes for TAPEPOOL and COPYPOOLS. this system is running TSM 5.2.2. We have run out of tapes as the setting for collocation (yes) is trying to use a tape for each node (as I understand it, ,,please correct me if I am wrong).. We have decided that since we have about 80 volumes with less then 1% utilized and 20 or so with large utilization %'s to set COLLOCATION=NO for the TAPEPOOL and COPYPOOLS. We are expecting to add another set of nodes and don't wish to consume more of our volumes (with small percent utilization) as we add the nodes. Question .. Will this setting COLLOCATION=NO stop the addition of volumes? (I expect the answer is YES,, please correct me if I am wrong.) Now to the second question. I see no easy way to have Space Reclamation condense the volumes included in the two pools as it will only process "FULL" volumes. (Again Please jump in here). QUESTION: is it acceptable to set the status from "FILLING" to "FULL" for the volumes with low percentage utilized to force Space Reclamation ? OR is there an easier way to accomplish the GOAL of reducing the number of volumes needed for the pools? (given that we have set COLLOCATION=NO) or should we simply wait out the natural filling of the volumes and allow normal Space Reclamation as time proceeds? Has anyone done this in the past? How have others dealt with this?? Thanks for any input.